Hong Kong launched a mass coronavirus testing scheme, but calls for millions to take up the offer have been undermined by deep distrust of the government following China's crushing of the city's democracy movement.

According to AFP, the free voluntary tests are part of an attempt to stamp out a third wave of infections that began in late June and saw the densely populated city reimpose economically painful social distancing measures.

But the programme has been hampered by a limited response due to the involvement of mainland Chinese testing firms and doctors — and swirling public fears of the harvesting of data and DNA as Beijing cracks down on calls for democratic reform.